Smelling a candle without burning it. If you can smell the fragrance whilst the candle is "cold" then the candle is said to have a good cold throw.
A candle with a good cold throw can provide a subtle fragrance in a small room.
The scent given off by a candle whilst it is lit, or essentially "hot". This is the whole purpose of buying the candle and if the candle doesn't give a good hot throw it isn't performing as you need it to.
This is the liquid wax on top of the candle. Candles need to be lit until the wax pool reaches the edge of the container to give the best performance on your current burn as well as future burns. The wax pool should also be no more than 20mm deep or your candle is at risk of getting too hot.
If a candle doesn't create a large enough wax pool, or is only lit for a short period, then a candle can tunnel. This is where wax isn't consumed around the edge of the container and a "tunnel" is created in the middle of the candle. Whilst not only consuming all of the wax, the candle may also drown and not reach its full burn time
Caused by too small a wick being used, so it is drowned out by the wax. In this case, the candle will likely have a small flame, not give off a very good fragrance throw and peter out before the wax has been consumed.
A candle can also drown if the candle tunnels due to not allowing the wax to reach the edge of the container on any of its burn cycles.
Self extinguishing wicks
If your wick has gone out on its own mid-burn then it is said to have self-extinguished.
This can happen if the candle has drowned due to an incorrect wick selection (too small) or your candle has tunnelled (wick too small/not burned to the edge previously). Another cause is burning your candle in a draught which is not a good place for your candle to be.
A candle remembers where the wax pool was the last time it was lit. This is called candle memory as the candle will then only pool as wide as it reached on previous burns.
Therefore, if you don't burn the candle until the pool reaches the edge of the container then next time it will likely only go as far again.
The total length of time a candle should burn for if cared for and burnt in 2 to 4 hour cycles.
Not the Friday night sort! This is clubbing of the wick and is often caused from either having too large a wick in the candle or the wick length being too long when lit. Always trim the candle wick(s) to 5-8mm before each burn cycle.
Clubbing can also be caused by having a candle burning in a draught which affects the efficient burn performance of the candle.
A burn cycle is the time from lighting the wick until it is extinguished. Each cycle should be for a minimum of 2 hours and a maximum of 4 hours.
This is where the candle produces black soot which means the candle is not burning efficiently. There is a misconception that this is limited to paraffin wax candles but it does apply to natural wax candles too. A good performing candle, with a good steady flame, burnt away from draughts or other sources of heat, will not produce excessive soot.